new scrubber

[180rftank]

I have made some changes over the last month to my horizontal scrubber and it seems to be dialed in perfectly now. Water flow was increased dramatically, angle was increased, as well as the correct lighting(4 39w ushio t5 3000k). I just cleaned the screen for the first time(brown algae, some green,not a lot of growth though), and have heard through reading that the general consensus is to increase feedings, and do not do a water change to promote growth on the ATS. This makes me very nervous with all the expensive corals I currently have. I have also turned off my skimmer as of about a week ago. Any words of wisdon from anybody would be greatly appreciated.

[Amphiprion]

Pick up the feeding if you've attended to all other potential issues. I was having the same issues until I increased the amount I fed. I would literally only get a light brown dusting over the screen and nothing else. These scrubbers actually allow you to feed quite a bit. I'm dumping in pellets + 1 full cube of frozen fish food just for 2 clowns, not counting several mL of phytoplankton I add, along with the rotifers and cyclops--all for the corals. Growth on the screen is steady and nutrient levels are steadily very, very low.

[SantaMonica]

If anything you should have been nervous when you ran your skimmer... it keeps corals on the verge of starving. Corals will now be happier, as in the ocean, where planktonic phyto is 90% of all ocean life, and where food is high, and N and P low. Just like your tank will be now.

However, never wait one month to clean. New growth will fill in faster after you clean the old stuff off.

I hope your screen is rough.

[180rftank]

ok, no problem with the scrubber, but should I discontinue water changes? I would normally do a water change every 2 weeks about 15-20% I cleaned my screen 2 days ago, and just looked at it a bit ago, and just only starting to turn brown. I have cranked up the feeding to 2x per day as well.

[rygh]

Remember that there are 2 reasons to do water changes.
- First, to remove/dilute the crud.
- Second, is to add back various nutrients that your tank biology is depleting.

I will let the serious ATS experts comment on the first point.

On the second point:
The reef basics, like calcium and alkalinity, are pretty easy to test and supplement.
Maybe iodine, strontium, and magnesium with some good test kits.
But the others are pretty much a wild guess. Never trust those miracle additives in a bottle.
And never supplement what you cannot test.

So discontinuing water changes totally is definitely not a good idea.

On the plus side, math is on your side, a 10% change does quite a bit for "addition", but a lot less for "dilution"

[SantaMonica]

If you would put kalk (lime) powder into your FW, you would get your cal and alk continuously. Then you just need mag (I personally don't use much mag). You can get kalk (lime) powder at any grocery, or here: http://store.mrswagesstore.com/mrswagpiclim.html

If you use kalk (lime) like this, then your reason for waterchanges becomes to reduce nitrate and phosphate, since you can add mag periodically. So, if your scrubber is working, you won't have to do water changes any more for this purpose. My strontium is always low, but whether I supplement it or not, does not seem to make any difference. Even after dosing, it's low again in a few days. Everything else is contained in the food you feed, especially iron if you feed nori.

As for feeding more, don't do that until your nitrate and phosphate start coming down. Have you been measuring? Without seeing your scrubber and growth, it might be that you built it wrong and it's not operating at all. In that case feeding more won't help. If you built it right, on a 180 gal reef tank, you should be able to grow one pound of algae (wet) every week. Yes, you should be able to remove 16 ounces of algae off your screen every week. At this level of growth, you can then feed a lot, and have no nuisance algae in your display.

[180rftank]

Phosphate...barely detectable, if at all
Nitrate...less than 10
Running a calcium reactor so PH is a steady 8.1 - 8.2
calcium...440-450

currently feeding on a daily basis...2 cubes of various frozen in AM, some various dry in PM, and every other day a chunk of Nori
Liquid feeding...recomended dosage on bottles...bio plankton every other day and reef solution every day in between. Would be happy for any other liquid feeding suggestions other than what I listed.

I probably should start dosing Mag again since water changes may be less frequent?

Now for the scrubber:

http://s997.photobucket.com/albums/af91/jm2drvr/ats/

This was basically a old acrylic aquarium that I had for a frag tank that I cut out so I could get a horizontal tray into. Water supply is at least 400+ gallons per hour on a 11.5 x 33 screen. The screen has some hi spots from running the saw blade over, but for the most part, the water flows perfectly over the screen. You can see after 3 days the screen showing some growth of mainly brown algae. The main tank has some algae(green hair) growing in it as well, not a ton, but definately has some throughout the whole tank.

Photos may be hard to see, but yes the screen is rough. The 4 T5's 3000k 39w x 4 are about 4-5 inches off the screen.

HEEEEEEEEEEElP!!!!!!!!!! :mrgreen:

[180rftank]

And yes, I would be happy to have a vertical scrubber and would pay for 1 if Santa Monica would just hurry up and build a bigger one!!!!!!! :lol: :idea:

[SantaMonica]

Actually I think yours is going to do just fine. It's one of the few non-verticals that looks like it has enough flow, enough light, and a rough screen. By day 7 it will be time to clean.

[180rftank]

I purchases some new test kits because my old ones were just that, kinda old. With the new test kits, my phosphates and nitrates and not detectable. I tested two times with the same results. Could this be the reason I am seeing such slow growth on my screen. And with such little growth, should I still be cleaning every 7 days?

[SantaMonica]

Clean after 7 days, and see how next week looks.

[180rftank]

got some good growth going on now. You can definately see the growth slow down as you feed less. My last question I think I know the asnswer to, but will ask anyway...I seem to have almost eliminated the algae growth on the live rock, or at least slowed it down, but I do notice a lot of algae on my sand bed has begun to grow???

[SantaMonica]

Because of all the food settling on the bottom, and nothing to eat it.